package main

import "io"

type Socket struct {}

func (s *Socket) Write(p []byte)(n int, err error)  {
	return 0, nil
}

func (s *Socket) Close() error {
	return nil
}

func usingWriter(writer io.Writer)  {
	writer.Write(nil)
}

func usingCloser(closer io.Closer)  {
	closer.Close()
}

//func main() {
//	s := new(Socket)
//	usingWriter(s)
//	usingCloser(s)
//}